Most prior document processing systems optically read information from documents, which information may be stored if not used immediately for processing. Some systems may lift portions of the document in order to retain certain fields of information on the document, and the document may also be filmed with a microfilm camera at high speed to retain a copy of the entire document. To optically read and digitally store an image of the document generally requires a very large storage capacity and has not been practice for high speed document processors.
In facsimile systems, document information is transmitted to produce a copy thereof at a remote location. In this instance, it is not necessary for long time storage of the document as the document is reproduced as the information representative thereof is transmitted. In order to reduce the time to send such documents, various coding methods have been performed on the information. Such codes, sometimes referred to as run length coding, is used to compress the information; however when it is desirable to run documents and capture image at rates up to 2,000 documents per minute, it is necessary to temporarily store the information and rapidly code it prior to storage on disk. Prior systems have not had the capability of processing and storing images at such high speeds.